Pixel Perfect

VGA and DVI-I/HDMI video output with Indivision AGA MK2cr


I’m happy to be the owner of an old 14″ Commodore 1084s-D1 monitor which is perfect for retro Amiga gaming, but using the Workbench in higher resolutions is another epilepsy inducing story.

Sadly, the said monitor has not fared very well the past few decades in storage, and shows the expected symptoms of the old-age.

I might try to do some work on it at some point, but I’m afraid that the problems are not resolved by just simply replacing the capacitors. Replacement part(s) might be quite hard to come by.

Anyways — I came across this little device Indivision AGA MK2cr. It is basically a flickerfixer/scandoubler which can be fitted over the A1200’s Lisa chip.

It captures the signals and converts the video to digital (DVI-I) and analog (VGA) signals.

Maybe I can make due without the old barrel sized CRT monitor after all?

I ordered this directly from Individual Computer’s web shop.

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The Indivision AGA MK2cr
The LISA chip
The LISA chip

Installing it doesn’t require much — no excessive force needed,  just enough push to get a firm grip on the chip.

Plugged on top of the LISA
Plugged on top of LISA

The cable can be easily routed under the floppy drive, and thru the A1200’s empty trapdoor. The backplate can be modified to house the DVI connector.

You can also purchase a separate DVI jack compatible backplate.

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It all fits quite nicely

Closing the hood and giving it a try.

First — the VGA output.

VGA
VGA signal output

I noticed quite horrible ghosting (not visible in above photo) and interference in the analog VGA output.

Similar issues are apparent in the digital signal.

Digital DVI output
Digital DVI output

My monitor is definitely not a quality one, and I’ve had issues also with my Mac, PC and PS4 — nothing this severe though.

I downloaded the AGA MK2cr’s config tool and available cores to check all the configuration options.

There seems to be quite many options to tune 😉

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Indivision AGA MK2 Preferences

First thing I did was to remove concurrent output of both VGA and DVI signals. I switched to use only VGA.

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Output options

That got rid of the major interferences in analog VGA signal.

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Clear VGA output

The video output is actually crystal clear, the photo above doesn’t really do it justice.

The DVI digital signal problems are not completely sorted out yet, but I will give it a try with another monitor or TV.

I believe that my monitor just doesn’t support the current HDMI signal setup — I need to continue tweaking the config tool.

People have also shared their AGA MK2 configuration files, which might solve the few problems I have noticed so far — like the not-so-smooth scrolling and problems in centering the screens.

This seems like a good 50hz  config for gaming.

Check out this guide also.

This configuration is also worth giving a try.

I’ll probably post my configuration here in the future, or a link to the one I have found most optimal for my setup.

Conclusion

I was hoping to have a fit-for-all solution with AGA MK2cr, but instead I’m reading thru endless forum threads dwelling into mysteries related to the configs and esoteric PAL/NTSC screen problems.

Sadly seems that the vendor has obviously given up on improving the configuration tool.

I’m going to give this a proper try — getting stuff like this to work was not supposed to be easy, right?

I can always fall back to the SCART option for gaming purposes.

Update 8.11.2016:

I have managed to get a decent setup for casual Workbench use.

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Nice and spacious Workbench desktop

See monitor drivers for the SuperPlus and HighGFX modes – packages available here and here.

I’ve had good experiences with HighGFX with 1024×768 resolution, but seems that some Amigas work better with higher graphic modes than others.

My setup start to flicker quite badly after 5 minutes from the initial cold boot. The flickering  goes a way completely after about 10 minutes.

Go figure.

Scotty, We Need More Power!

Upgrading the Amiga 1200 with ACA1233n 40Mhz


This little piece of accelerated coolness arrived in the mail today.

ACA1233n

The CPU speed is not the necessarily the most important feature — the amount of memory is the thing.

Additional memory allows you to do cool things like setting up WHDLoad for gaming directly from the Workbench.

The ACA1233n packs whopping 128MB of memory.

The obligatory list of  specifications:

  • For Amiga 1200 and Amiga 500 with ACA 500
  • Full 68030 with MMU running at 40MHz
  • 127MB Fast Memory (32-bit) with burst mode support
  • 1MB reserved for MapROM feature
  • Dynamic clocking for power-saving
  • Card enable/disable in software
  • Memory available to onboard CPU if accelerator is switched off (not ACA 500)
  • Faster clockport for RapidRoad gives 55% speed increase
  • New software compatibility settings
  • Improved A1200 compatibility
  • PCMCIA compatible

I decided to also include the RTC (Real Time Clock) shield to retain the system date and time  between restarts.

The RTC shield can be used also without the accelerator card, and can be connected directly to the motherboard.

Installation was really easy — no tools required.

Done installing

The ACA1233n was listed properly in the Expansion Board Diagnostics. Check the Amiga Hardware Manufacturer Registry.

You can get into the boot options by holding left and right mouse buttons during the boot.

First boot

The ACA1233n does a good job in configuring itself. I didn’t need to run any additional configuration utils, or install any libraries to get the basics working.

Avail and cpu
ShowConfig

I didn’t notice any heat related issues. The 68030 did get a little warm after longer period of use, but nothing compared to the typical temperatures of today’s CPUs or video cards.

Sadly the ACATune application doesn’t seem to support the ACA1233n. Running it brings up the Guru Meditation.

I would especially want have the MapROM  functionality working. The idea is to load the ROM contents into memory — this should increase the overall system performance significantly.

Some alpha/beta release tools seems to exists for enabling the MapROM — need to give them  a try bit later.

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Sysinfo stats

Now, off to do some proper WHDLoad gaming…

Lifting the Skirt

Before powering the Amiga I wanted to check the state of the internals


It’s always a good idea to have a quick peek of the overall condition of the hardware before powering it up for the first time — especially as it may have been laying dormant for few decades.

Seems that someone has been here before

Commodore really played it safe with the RF shielding of the unit. I have seen microwave ovens with less RF shielding than this…

RF-shieding

My Amiga didn’t come with a 2.5″ hard drive so I added the IDE CF drive, which was something I was planning to do anyway.

Of with the shielding

The overall condition of the motherboard is really good. No leaking caps or burnt out resistors in sight.

Absolutely no corrosion on the motherboard — as it had just arrived from the factory. Seems that the unit has also been recapped at some point.

The motherboard revision is 1D4 which was the last revision made by Commodore, the later ones made by Escom were 2B.

A1200 motherboard revision details

For the common timing issues and related fixes check this.

Other details on motherboard revisions are available here.

The previous owner of this Amiga had done a brilliant job of keeping the old lady in good shape.

Interesting design choice for the mouse port

Nice to see the original quality assurance markings made the assembly line workers some twenty odd years ago.

QA Markings

Let’s get the Amiga started — I couldn’t find any issues on the Amiga nor the power brick.

After partitioning the HD and installing Workbench using WinUAE, I had the Amiga boot up just fine.

Avail and cpu details

The specs of A1200 — there is still quite some room for improvement here 😉

The Amiga Has Landed (again)

Amiga makes the mancave


I bought the classic Commodore Amiga 1200 from an online auction site while ago.

It has now arrived, and I’m happy.

Amiga 1200

I actually never had this third-generation Amiga model, which sadly became known as the last affordable consumer Amiga Commodore released before declaring bankruptcy in 1994.

Commodore A1200 Badge
A bit of personal history

My first exposure to computing was the venerable Amiga 500 back in the late ’80s. I was the cool kid with a home computer capable of producing amazing graphics and actual multi-channel stereo music and sound effects.

Shadow of the Beast almost drive one of my friends into insanity.

After few odd years the coolness started to die down, as I was not able to play Doom on my beloved Amiga. The other kids in my neighbourhood had access to their dads’ work PCs with hard-drives and happily played Wolfenstein and Doom on a screen scaled down to the size of a matchbox.

I believe that 3d games played a major role in the demise of Amiga, and the Amiga gaming community.

Check this great video related to the Amiga FPS games — and the apparent limitations caused by the Amiga HW.

For me having an Amiga meant creating music, graphics and collaborating in games programming. I was never a huge gamer myself.

I accessed my first email account using Amiga back in 1994. I had managed to talk my dad around into buying a blazingly fast 14400 baud modem for the purpose of paying bills thru online banking services — I don’t think that he ever did.

My first exposure to programming was AMOS, which was the gateway drug to C and 68k assembler.

The level of access you had to poke the hardware is something missing from today’s systems, and still makes the Amiga architecture an interesting platform to develop onto.

A history of the Amiga — Ars Technica’s insightful series of articles about Commodore and Amiga history.

What next

After I have revisited majority of my childhood gaming memories, I’ll try obtain some modern upgrades — and pimp-up the Amiga 🙂

First — I need to figure out how to properly connect the Amiga to my flatscreen TV.

This composite shit won’t do!

Sadly it’s not a “retro” filter.

Welcome to Retro Hardware Stuff

I have started Retro Hardware Stuff blog about my adventures into old-school computing and hardware


I’m hoping to start some restoration projects, write about my progress and provide some details of the problems I might — and presumably will run into.

This blog will probably focus mostly on good old Commodore hardware, but I also have some Nintendo gaming systems in desperate need of repairs and restoration.

I will also try to have some time to look into programming for various platforms. Especially the low-level stuff like assembler.

Lets see how this turns out…